Supports update/remove of physical/vlan/dpdk interfaces in OpenstackNode app.

Change-Id: I7c3ab11ee90778fb2c842cb2805947f5a1d2c841
diff --git a/apps/openstacknode/app/src/main/java/org/onosproject/openstacknode/web/OpenstackNodeWebResource.java b/apps/openstacknode/app/src/main/java/org/onosproject/openstacknode/web/OpenstackNodeWebResource.java
index 3c1a263..1b69f30 100644
--- a/apps/openstacknode/app/src/main/java/org/onosproject/openstacknode/web/OpenstackNodeWebResource.java
+++ b/apps/openstacknode/app/src/main/java/org/onosproject/openstacknode/web/OpenstackNodeWebResource.java
@@ -169,7 +169,7 @@
 
                      nodeSet.add(openstackNode);
                  } catch (Exception e) {
-                     log.error(e.toString());
+                     log.error("Exception occurred due to {}", e);
                      throw new IllegalArgumentException();
                  }
              });